The most heavily Christian countries on Earth

Billions of believers

Christianity is the most widely practiced religion in the world, with some 2.4 billion followers -- one-third of the global population. The Catholic church alone has 1.09 billion followers.

The United States has the largest Christian population in the world, but not the highest rate of Christians per capita. In fact, the U.S. population, which is about 71 percent Christian, according to the U.S. State Department, doesn't even make this list, ranking in 85th place worldwide.

See which countries have the largest percentage of Christians, according to various census results, the Pew Research Center and other sources.

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61 (TIE). El Salvador

We'll start with El Salvador, where the population is 81.9 percent Christian.

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61 (TIE). Ukraine

Ukraine's population is 81.9 percent Christian. Most belong to a branch of the Orthodox church.

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60. Swaziland

Swaziland's population is 82.7 percent Christian.

Credit: Catholic Diocese of Umzimkulu

57 (TIE). Costa Rica

Eighty-three percent of the population of Costa Rica is Christian, primarily Catholic.

Here, believers carry a statue of Jesus during a procession known as Jesus Nazareno of the tapes, during Holy Week in 2017. People tie ribbons to the statue to symbolize promises they make to Jesus.

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57 (TIE). Dominican Republic

Eighty-three percent of the Dominican Republic is Christian, primarily Catholic.

Credit: Miguel Gomez/AP

57 (TIE). Italy

Italy's population is 83 percent Christian More than 81 percent of the population is Catholic.

Here, Pope Francis leads a Mass at the church of San Tommaso on the outskirts of Rome in 2014.

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56. Ireland

Ireland's population is 83.8 percent Christian.

More than three-quarters of residents in the Republic of Ireland identify as Catholic, while in Northern Ireland, the 2011 census found 48 percent of the population identifies as either Protestant or brought up Protestant and 45 percent as Catholic or brought up Catholic.

This photo shows a Saint Patrick's Day celebration at Saul Church on March 17, 2017, in Downpatrick, Northern Ireland.

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55. Portugal

Portugal's population is 84.3 percent Christian, and 81 percent Catholic.

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54. Liechtenstein

The population of Liechtenstein is 84.4 percent Christian, and nearly 76 percent Catholic.

Credit: Arno Balzarini/AP

53. Nicaragua

Nicaragua's population is 84.6 percent Christian, Nearly 60 percent of the population is Catholic.

Here, the faithful take part in Ash Wednesday observances at the cathedral in Managua.

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51 (TIE). Bulgaria

Eighty-five percent of Bulgaria's population is Christian. Most belong to the Eastern Orthodox Church.

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51 (TIE). Philippines

Eighty-five percent of the population of the Philippines is Christian and 80 percent is Catholic.

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50. Kenya

Kenya's population is 85.1 percent Christian. Protestant denominations, including the Anglican Church of Kenya, have the largest membership.

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49. Liberia

Liberia's population is 85.5 percent Christian.

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45 (TIE). Cook Islands

The population of the Cook Islands in the South Pacific is 86 percent Christian.

Credit: AP

45 (TIE). Monaco

Monaco's population is also 86 percent Christian.

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45 (TIE). Bahamas

Eighty-six percent of the population of the Bahamas is Christian.

Credit: Andres Leighton/AP

45 (TIE). Argentina

Argentina's population is 86 percent Christian, and 71 percent Catholic.

Here, priest Juan Gabriel Arias shows a tattoo depicting Christ holding the Racing Football Club shield at the church Natividad de Maria in Buenos Aires. The priest became member of the executive committee of the Racing Club after getting permission from Cardinal Jorge Bergoglio, now Pope Francis.

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42 (TIE). Zimbabwe

Eighty-seven percent of Zimbabwe's population is Christian.

Credit: Jekesai Njikizana/AFP/Getty Images

42 (TIE). Peru

Peru's population is 87 percent Christian and 77 percent Catholic.

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42 (TIE). Guatemala

Eighty-seven percent of the population of Guatemala is Christian; 77 percent of the population is Catholic.

Seen here, Ash Wednesday in Guatemala City on March 1, 2017.

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38 (TIE). Aruba

Eighty-eight percent of Aruba's population is Christian, the vast majority Catholic.

Credit: Luis Acosta/AFP/Getty Images

38 (TIE). Gabon

Eighty-eight percent of Gabon's population is Christian.

Here, a choir sings hymns during a rally of the Catholic Charismatic Renewal Church in Owendo in 2014.

15. Seychelles

The population of Seychelles, an island chain in the Indian Ocean, is 94.7 percent Christian.

Credit: Seychelles Ministry for Youth Sports and Culture

14. Moldova

Moldova's population is 95.3 percent Christian. The Orthodox Church is by far the largest here.

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12 (TIE). Faroe Islands

The population of the Faroe Islands, in the North Atlantic, is 95.4 percent Christian. The largest denomination is Evangelical Lutheran.

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12 (TIE). Micronesia

The population of Micronesia, a federation of islands in the Pacific, is 95.4 percent Christian.

Credit: Visit-micronesia.fm

11. Zambia

Zambia's population is 95.5 percent Christian.

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9 (TIE). Paraguay

Paraguay's population is 96 percent Christian.

Here, Catholics throw money from a church tower in gratitude for favors received from the Virgin Mary.

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9 (TIE). Haiti

Haiti's population is 96 percent Christian, primarily Catholic. Many Haitians practice the tradition of voodoo as well as Christianity.

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8. Greenland

Greenland's population is 96.6 percent Christian, almost entirely Protestant.

Credit: Getty Images

7. Papua New Guinea

Papua New Guinea's population is 97 percent Christian.

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6. Grenada

The Caribbean nation of Grenada's population is 97.3 percent Christian.

Credit: Harold Quash/AP

5. Armenia

Armenia's population is 97.9 percent Christian. Almost all belong to the Armenian Apostolic Church, which was founded in the first century A.D. Armenia became the first nation to declare Christianity as its state religion in 301 A.D.

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3 (TIE). Greece

The population in Greece is 98 percent Christian, almost all Greek Orthodox.

Here, a Greek Orthodox worshipper prays during a Good Friday service.

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3 (TIE). Romania

Romania's population is 98 percent Christian, mostly Orthodox.

Here, Romanians pray during a Palm Sunday service outside of a Greco Catholic church.

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2. East Timor

The Democratic Republic of Timor-Leste (East Timor), in Southeast Asia, is 99.1 percent Christian. Nearly 97 percent of the population is Catholic.

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1. Vatican City

The population of Vatican City -- home of the pope, St. Peter's Basilica, the Sistine Chapel and the Vatican Museums -- is 100 percent Catholic. Vatican City, an independent city-state of just over 100 acres located within Rome, has a population of about 1,000 people.